Method of and apparatus for building sea walls



Feb. 10, 1942. J. a. BROCKHURST 2,272,236

METHOD OF AND APPARATUS FOR BUILDING SEA WALLS Filed Nov. 17, 1957 s Sheets-Sheet 1 E1 HII' INVENTOR BY -E f iM ATTORNEY Feb. 10, 1942. J. B. BROCKHURST 2,272,236

METHOD OF AND APPARATUS FOR BUILDING SEA WALLS Filed NOV. 17, 1937 3 Sheets-Sheet 2 -|NVENTOR ATTORNEY Feb. 10,1942. BROCKHURST I 2,272,236

METHOD OF AND APPARATUS-FOR BUILDING SEA WALLS Filed Nov. 17, 1937 3 Sheets-Sheet 3 5- am Y.

' ATTORNEY .INVENTOR Patented Feb. 10, 194-2 UNETD STT :T OFFICE METHOD OF AND APPARATUS Eon BUILDING SEA wALLs Claims.

This application is a continuation-in-part'of my application for Letters Patent filed May 21, 1934, Serial No. 727,449. The invention relates to improvements in Method of and apparatus for building. sea walls and the like, such as breakwaters, groins, abutments, piers and other massive structures and foundations for said structures. These usually extend from the short or sea line into progressively deeper water, although in the building of an abutment or pier for a bridge, for example, the entire massive structure will be located beyond and outside of the shore line.

In carrying my invention into effect, I preferably first construct a cofier dam, preferably of interlocking sheet steel piling, said cofier dam extending from a sufficient height above the datum line a sufficient distance below the bottom as to prevent undermining. I then locate within this coffer dam a suitable form or mold in which is cast a concrete block of massive size. The dimensions of these blocks depend upon the special conditions and the forces to which the structure as a whole is to be subjected.

With the specific form of the invention disclosed in my said application, outside of the mold or form and between the sides thereof and the coffer dam vertical discharge channels are presented through which sand, gravel, or other insoluble material supporting the block, may be ejected to permit the lowering. of a block by grav ity when the same has set. With the present form of the invention, this ejection of the sand, gravel, or other insoluble material will be effected through a central opening in the block, instead of exteriorly of the block as-specifically illustrated in my said application. 1

I prefer to effect this removal of the gravel, sand, or insoluble material by means of jets of compressed air and preferably also by a stream or streams of water under pressure through pipes projecting vertically through the block or blocks, although as I point out in said application when a very massive block is to be lowered to a depth too great for the removal of the material. beneath by air and water pressure, the vertical central passage may be increased in size to permit the operation of a clam shell bucket for the removal of said material.

Except in the respect that the gravel, sand, or other material is removed centrally of the block instead of exteriorly thereof, the present method and apparatus follow the description in said application, for a better understanding of which reference should be made.

However, in the present application certain additional features will be described or shown but not claimed and will be made the basis of later divisional applications based upon the present application.

In order that my invention may be better un-' derstood'reference should be had to the accompanying drawings forming a part hereof and in which Figure 1 is a top plan of the apparatusshowing a portion of a sea wall constructed in accordance with my invention and illustrating the casting of one of the massive blocks.

Figure 2 is a section of the same on the line 2-2.

Figure 3 is a sectionalv view on line 3-3 illustrating the lowering of the first or bottom block of a tier.

Figure 4 is a similar view illustrating the operations which are performed immediately before the completion of lowering th second block, the parts being in position to receive the concrete from which the third block is to be formed. Figure 5 is a plan view illustrating the lowering of a massive block by means other than. air and/or water jets and with the use of the cotter dam.

Figure 6 is a section onthe line 5-6. of Figure 5. A

In all of the above views corresponding parts are represented by the same reference numerals.

i represents generally a suitable apparatus for handling the interlocking steel sections and the pressure pipes and mold, preferably carried on endless driving members 2 of the caterpillar type and provided with a pivoted boom 3 over which extends a cable 4 leading to a Windlass 5.

6' represents the cofier dam, made preferably of interlocking steel panels with plane webs and extending down into the bottom belowthe level of the sea wall as shown particularly in Fig,- ures 3 and 4. At the front of the coiier dam in line with the tier of blocks under construction is a metal mold 6" formed with vertical troughs-l, at the front and with a single vertical trough 8 at the rear, whereby the cast block will be formed with interlocking tongues and grooves as I describe in my said application.

The mold also supports the horizontal troughs 9-99 which limit and define the upper surface of the block and prevent overflow of the concrete mass when in a plastic condition.

Extending down from the top of the mold is an inclined latticed beam [-0 for supporting an extension ll of the mold, in which is cast a concrete block [2 acting as a counterbalance. Carried by the block I2 is an airtank l3, which I prefer to use in order to equalize the air pressure and leading into this tank is an air pipe 14 from a suitable compressor.

As with my said application, each block is formed with a central tube 15 closed at its upper end and which extends above the block and leads to a discharge pipe 16 through which the gravel, sand or other material is ejected. As the blocks descend additional sections of the tube i5 are added, being held in place by any suitable form of tight coupling 11, as shown in Figures 3 and 4.

As with my said application, the lowermost block is preferably formed with a conical-shaped bottom constituting a chamber below the de scending block or blocks.

Within th pipe or tube I5 is the airpipe l9 and water pipe 29, one behind the other as shown in Figure 2.

A pipe 2i extends from the pressure tank l3 to the airpipe I9. These pipes are supported by a hook 22 connected with the cable 4. As with my said application, gravel, sand or other material 23 is introduced within the cofier dam so as to extend to a level somewhat above the lower end of the mold 6, whereupon by introducing jets of water and compressed air through pipes I 9 and 20 this sand or other material will be scoured out and escape through the pipe I 5 and discharge pipe Hi. The removal of this material from beneath the block, will cause the block to descend by gravity almost to the bottom of the mold whereupon a new block will be cast and after the same is hard the same operations repeated. Pipes 24 may be used to discharge the plastic concrete mix into the mold through the openings formed between the troughs 9-9, or said pipes may be employed to supply the initial mass of sand or other supporting material.

The operations are exactly the same as with my said application, except that instead of driving out the gravel, sand, or other material through passages between the mold and coiler dam and between the descending blocks and the coiler dam, I cause this'material to be removed through a central opening in the blocks in which the pressure pipes are preferably located. Ordinarily a certain amount of leakage takes place in the coffer dam and if this leakage is suflicient to keep a supply of water beneath the block compressed air alone may be relied upon to perform the securing action. A separate jet of water is however preferable. It will be evident that in order to carry out the operation in this way the sand, which flows very easily, must be supported laterally by the caisson and there must be substantial resistance to upward movement between the lowermost block and the coffer dam, due for example to the relatively close fit of the block in the cofier dam. Due also to the introduction of pressure fluid downwardly substantially along the vertical axis of the lowermost block, the fluid jet thus provided will tend to remove the sand below the block in such a manner as to form an opening in the form of an inverted cone, the scoured out sand rising through the central opening in the block. The shape and position of the inverted cone will depend upon the velocity of the fluid. It will be seen that the descending block acts in connection with the cofier dam to prevent the fluid and sand from breaking out beneath the edges of the block, and that, in order to produce upward flow through the central passage in the block, the lower ends of the scouring pipes should be higher than the bottom of the block. This the block will be maintained in equilibrium during its settling movement.

In Figures 5 and 6, I illustrate the carrying out of my improved method with very massive blocks, where the material to be removed from beneath the block is handled by other means than by jets of compressed air and high pressure water. As shown the sea bottom or other locality is indicated at 25. Upon the bottom is erected the coifer dam E extending a suificient distance below the bottom as to prevent undermining and carrying a mold 6" at its upper end in which the massive block 27 is cast. Within the coifer dam and extending into the mold as shown is placed a mass of sand or other suitable supporting material 23 supporting said block. 28 is a central opening within the block of sufiicient size to permit the operation of a clam shell bucket or other element 29 for the removal of the material which supports the block. As this material is removed the block will descend by gravity as is obvious.

Having now described my invention what I claim is new therein and desire to secure by Letters Patent is as follows:

1. The method of constructing a concrete-block seawall or the like which consists in erecting at the front end of a stationary supporting structure a coiier dam having said front end as one side thereof, said coifer dam extending below the desired level of the bottom of the sea wall, in casting in a mold at the upper portion of said cofier dam a concrete block having a vertical passage extending from the bottom to the top thereof and having its rear wall in substantially the same plane as the front surface of said supporting structure, in filling the coffer dam and 40, the bottom of said mold with material such as sand and gravel, so as to support said block and in securing out material from beneath the block and removing the same, centrally of the block.

2. The method of constructing a sea wall or the like which consists in erecting at the front end of a stationary supporting structure a coiier dam extending below the desired level of the bottom of the sea wall, said cofier dam having said front end as one side and at the edges of said front end sides substantially in alignment with the sides of said supporting structure, in casting a concrete block in a mold at the upper portion of said coifer dam of substantially the same cross section as the cofier dam so that the block in its downward movement will be guided by the coifer dam, said concrete block being formed with a central passage from the bottom to the top thereof, in filling the cofier dam and the bottom of said mold with material such as sand and gravel so as to support said block and in scouring out material, by means of a jet of fluid under pressure, from beneath the block and removing the same centrally of the block.

3. The method of constructing a sea wall or the like which comprises erecting at the front end of a stationary supporting structure a coffer dam extending below the desired level of the bottom of the sea wall, said coffer dam having said front end as one side and at the edges of said front end sides substantially in alignment with the sides of said supporting structure, casting in a mold at the upper portion of said coiier dam a concrete block of substantially the same cross section as the coffer dam so that the block in its downward movement will be guided by the coiler dam, said concrete block being formed with a central passage from thebottom to the top thereof,. filling the cofier dam and the bottom of said mold with material such as sand and gravel so as to support said block and in scouring out material, by means of a jet of fluid under pressure, from beneath the block and removing the same centrally of the block to lower the block and bring its top to the level of the top of said supporting structure, casting a second block on the top of the first block with a central passage forming an extension of the first and sinking the two blocks in the same manner as the first to bring the top of the second block to the level of the top of the supporting structure, removing the front wall of the caisson, extending the side walls of the caisson to form the lateral walls of a new caisson section, forming the front wall of the new caisson section, filling the new caisson section with material such as sand or gravel, casting one or more blocks in the mold in its new position and sinking the blocks in succession so that each block serves as the bottom of the mold in casting the next block.

4. Apparatus for constructing a, sea wall 'or the like comprising a cofier dam extending below the level of the bottom of the sea wall to be constructed, a concrete-block mold at the upper end of said coiier dam and of substantially the same cross section as said cofier dam to cause a block cast in said mold to be guided closely in its downward movement, a body of material such as sand or gravel in said caisson to form the bottom of said mold, means in said mold to provide an upwardly extending central passage through a block cast in said mold and means for scouring out material from beneath the block and removing it centrally of the blocks.

5. The method of building sea walls and like structures which comprises constructing a cofier dam extending below the desired level of the bottom of the seawall and enclosing at its bottom a desired area of the sea bottom, partly filling the cofier dam with sand, supporting upon the enclosed sand a massive concrete block adapted to substantially cover said area at the bottom of the cofler dam and provided with a central vertical opening, and lowering the block by removing the supporting sand from beneath the center of the block toward the sides of the cofier and presenting it to the central opening in the block to be removed therethrough whereby the block moves down by gravity upon a progressively eroded bottom edge support maintained in position by the coder dam.

6. The method of building sea walls and like structures which comprises constructing a coffer darn extending below the desired level of the bottom of the sea wall and laterally sealing a desired area of the sea bottom, partly filling the coffer dam with sand, supporting upon the laterally sealed sand a massive concrete block adapted to substantially cover said area at the bottom of the cofier dam and provided with a vertical central opening, introducing streams of air and water under pressure downwardly through the central opening in the block and into the body of sand within the laterally sealed space beneath the block whereby substantially all of the scouring fluids are obliged to move upwardly through the central opening of the block and carry the supporting sand from beneath the block upwardly through said central opening, whereby the block moves down by gravity.

'7. The method of building sea walls and like structures which comprises erecting a cofier dam to seal laterally a desired area of the sea bottom extending to a level below that desired for the bottom of the proposed structure, partly filling the cofier dam with sand, supporting upon the laterally sealed sand a massive concrete block of substantially the cross sectional area of the cofier dam and provided with a vertical central passage comprising at its lower end a conical chamber, and lowering the block by streams of fluid including air and water introduced downwardly through pipes in said central passage into the body of sand within the laterally sealed chamber beneath the block, whereby substantiallyall of the scouring fluids are caused to move upwardly through the vertical central passage in the block and carry upwardly therethrough sand from beneath the block to enable the block to move downwardly by gravity.

8. The method of building sea walls and like structures which comprise erecting a cofler dam to seal laterally a desired area of the sea bottom extending to a level below that desired for the bottom of the proposed structure, partly filling the cofier clam with sand, supporting upon the laterally sealed sand a massive concrete block of substantially the cross sectional area of the cofier dam and provided with a vertical central passage comprising at its lower end a chamber having a relatively small cross-sectional area at its top but increasing in cross-sectional area toward the bottom of the block, and lowering the block by streams of fluid including air and water introduced downwardly through pipes in said central passage into the body of sand within the laterally sealed chamber beneath the block to force the sand up through the central passage of the block and form an inverted conical space from which sand is being removed, the depth of the inverted conical space being determined by the velocity of the streams of fluid and the position of the lower ends of the pipes, said ends being above the bottom of the block.

9. The method of building sea walls and like structures which comprises erecting a coffer dam to retain against lateral movement material of a desired area of the sea bottom down to a level below the bottom of the proposed structure, partially filling the coffer dam with sand, supporting upon the enclosed sand a massive concrete block a cross-sectional area substantially equal to that of the interior of the coifer dam and having a vertical central opening, lowering the block by excavating centrally of the block to form in the sand beneath the block a chamber having a downwardly pointed tip and gradually increasing in cross-section toward the bottom of the block, and discharging the sand upwardly through the central opening of the block, whereby the block moves down by gravity and is balanced upon a progressively-eroded level bottom-edge support maintained in position by the cofler dam, thus maintaining the descending block in equilibrium.

10. The method of building sea walls and like structures which comprises erecting a coifer dam to produce substantial sealing of a desired area of the sea bottom against loss of material laterally, said coifer dam extending downwardly to a level below the bottom of the proposed structure, partially filling the cofier dam with sand, supporting upon the enclosed sand a massive concrete block of substantially the same cross-sectional area as the enclosed sand and having a vertical central opening and a concave bottom, and introducing streams of fluid under pressure downwardly through the central opening in the block and into the laterally sealed space beneath the block to erode the sand beneath the block in substantially the form of a chamber with a downwardly directed tip and increasing in cross-section toward the bottom of the block and to subject the sand to substan tially the full pressure of the scouring fluids to be discharged upwardly through said central opening, whereby the block moves downwardly by gravity while resting upon a progressivelyeroded bottom-edge support maintained in position by the coffer dam, and additionally seals the enclosed area against loss of pressure fluid laterally out of the sealed area, thus increasing the efliciency of the scouring operation.

JAMES B. BROCKHURST. 

